/*
* Copyright 20101 Red Hat, Inc. and/or its affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.drools.examples.sudoku;
import java.util.Set;
import java.util.HashSet;
/**
* Abstract base class for the three types of cell groups of nine cells.
*/
public abstract class SetOfNine {
private Set<Integer> free;
protected SetOfNine() {
free = new HashSet<Integer>( CellGroup.ALL_NINE);
}
/**
* Redefine the set of acceptable values for this cell.
* @param values the Integer objects representing the new set of acceptable values.
*/
public void blockExcept(Integer... values) {
free.clear();
for( Integer value: values ){
free.add(value);
}
}
/**
* Remove an Integer from the values still to be assigned to some cell of this group.
* @param i an Integer object
*/
public void blockValue(Integer i) {
free.remove(i);
}
/**
* Returns the set of Integers that still need to be assigned to some cell of this group.
* @return a Set of Integer objects.
*/
public Set<Integer> getFree() {
return free;
}
/**
* Returns the number of Integers that still need to be assigned to some cell of this group.
* @return an int value
*/
public int getFreeCount() {
return free.size();
}
/**
* Returns the first (only) permissible Integer value.
* @return an Integer object
*/
public Integer getFreeValue() {
return free.iterator().next();
}
}